Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description states 'modify a sequence in-place', which is a critical behavioral trait beyond the input schema. However, it does not disclose whether the function returns the shuffled array or None (as in numpy's shuffle). With no annotations provided, the description carries full burden, and this omission prevents a perfect score.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.